Apple is widely expected to launch two new iPhone 6s versions this fall that’ll be very similar to their predecessors when it comes to overall design. However, a well-connected insider who has been accurate with early details about previous iPhone releases says the iPhone 6s and iPhone 6s Plus won’t be exact replicas of previous models, and we should expect several key changes.

For starters, the new iPhone 6s will come with Force Touch-ready displays, meaning that an extra layer of sensors have to be placed on the display so the devices can tell the difference between standard and firm touches. KGI Securities Ming-Chi Kuo says the new phones will be 0.2mm thicker than the iPhone 6 because of that Force Touch display, according to Japanese Apple fan blog Macotakara.

Additionally, the iPhone 6s will be slightly taller (by about 0.15mm) and wider than the iPhone 6.

When it comes to color options, the iPhone 6s and iPhone 6s Plus will also be slightly different from their predecessors. The gold iPhone 6s will be closer to yellow gold, while space gray will be darker than it is on the iPhone 6. Apple also plans a rose gold iPhone 6s this year, Kuo said.

Finally, the analyst also said that the new iPhones will be made of 7000 Series aluminum, just like the Apple Watch Sport. Previous reports have also suggested that Apple wants to prevent any new “Bendgate” problems by strengthening the aluminum used for the iPhone’s case. Most recently, an Apple supplier hinted that it might be working on 7000 Series aluminum parts for the company.